It has been reported that extensive airborne tuberculosis transmission is associated with the treatment of patients in the process of sputum induction. In particular, extensive TB transmission has been associated with the employment of pentamadine aerosol treatments. HIV-infected patients tend to be at an increased risk of reacting to tuberculosis by virtue of aerosol airborne transmission. The transmission of the diseases to unsuspecting infected patients and to medical staff is enhanced by the coughing induced by aerosol treatments, such as pentamadine, wherein a nebulizer is connected to a free standing air compressor to generate aerosol particles of the chemical. In addition, aerosols produced by sputum induction, bronchoscopy and suctioning patients with artificial airways also may lead to the airborne transmission of diseases to other persons and staff breathing the same air. Therefore, it is desirable to remove an infectious aerosol produced by patients and also to remove airborne drug particles which may be produced when patients are treated with aerosolized forms of drugs. Typically, the medical treatments involving enhanced coughing or aerosol drug treatment of patients is carried out in rooms of adequate fresh air ventilation so as to decrease the probability of transmission. However, adequate ventilation alone cannot eliminate the risk of airborne transmission. Other techniques include carrying out the procedures in high level, ventilated areas with the air exhausted safely to the outside with negative room air pressure relative to the outside together with properly installed and maintained UV lights and with extensive and regular treatments and testing of the staff for airborne disease infection.
The hazards of airborne transmission and the occupational exposure for example to hepatitis B virus in human immunology and to other viruses has been recognized as a growing problem in occupational medicine, since the transmission of hepatitis or AIDS through sputum and saliva of a patient.
One technique for reducing the risk of airborne transmission of disease is to provide a booth approach, such as a enclosed chamber, designed to remove any infectious aerosols produced by the coughing of a patient which booth usually comprises an enclosed chamber having a seat for the patient and a back panel wall against which the patient sits and includes a prefilter, a blower and a high efficiency particulate filter. The back panel includes on its back portion a UV tube light to enclose a duct-like space and whereby on activation of the air blower, the air is drawn through the prefilter into the chamber while the patient is undergoing the aerosol treatment up over the back panel and through the duct-like space and exposed to the UV rays and through the hepafilter and then discharged into the environment.
While the booth approach may be satisfactory in some respects, the booth approach is not portable, thus it cannot be used for bedsides or non-ambulatory patients, and further is more expensive. More particularly, after treatment of the patient the booth still remains contaminated and thus there must be a period of time before the next patient can enter the enclosed booth.
It is therefore desirable to provide for a high efficiency, portable, quickly reusable respiratory filter apparatus and method.